A new halimane-type diterpenoid from the liverwort Jungermannia infusca

The isolation of 1(10)-halimadien-13xi-ol (1), a new diterpenoid from Jungermannia infusca, is reported.     

Four new bis-iridoids isolated from the traditional Tibetan herb Pterocephalus hookeri

Pterocenoids A–E (1–4), which Pterocenoids A(1) is one novel dimer containing a pyridine monoterpene alkaloid; and Pterocenoids B–E (2–4) are rare arranged non-glycosidic bis-iridoids were isolated from Pterocephlus hookeri. The structures of the compounds were established by 1D and 2D NMR spectroscopy and mass spectrometry. All bis-iridoids isolated from P. hookeri were found to possess secoiridoid/iridoid subtype skeletons. Hence, bis-iridoids can be regarded as the chemotaxonomic markers of P. hookeri. The origins of the new bis-iridoids (1–4) were postulated and their activities of inhibition of the NF-κB pathway were assayed and compounds 1–3 showed moderate activity in inhibiting NF-κB.     

Isolation,identification and necrotic activity of viridiol from Chalara fraxinea,the fungus responsible for dieback of ash

Investigation of secondary metabolite production of Chalara fraxinea, the fungus responsible for dieback of ash, led to the isolation of the phytotoxin viridiol and the fungistatic compound viridin. Viridiol showed necrotic activity towards ash‐seedlings.     

Armillaramide, a new sphingolipid from the fungus Armillaria mellea.

A new C(18)-phytosphingosine ceramide containing non-hydroxy fatty acid, armillaramide (1), has been isolated together with ergosterol peroxide from the fruiting bodies of the basidiomycete Armillaria mellea. Its structure was established as (2S,3S,4R)-2-hexadecanoylamino-octadecane-1,3,4-triol by spectroscopic and chemical methods.     

Kujigamberol, a new dinorlabdane diterpenoid isolated from 85million years old Kuji amber using a biotechnological assay

A new compound, 15,20-dinor-5,7,9-labdatriene-18-ol (1), named kujigamberol, was isolated from amber, fossilized tree resin from the Kuji area in Japan, has been dated as being 85 million years old (late Cretaceous). Kujigamberol was identified using the hypersensitive mutant yeast (zds1? erg3? pdr1? pdr3?) with respect to Ca²⁺-signal transduction. The structure was elucidated on the basis of spectroscopic analysis including 1D NMR, 2D NMR and HR-EI-MS. It was different from known diterpenoids with a similar activity isolated from Baltic amber (agathic acid 15-monomethyl ester (2), dehydroabietic acid (3) and pimaric acid (4)). Kujigamberol showed glycogen synthase kinase-3β (GSK-3β) inhibition activity involving the growth restored activity against the mutant yeast and was cytotoxic to HL60 cells (IC₅₀ = 19.6 μM).     

Stereochemical determination of new cytochalasans from the plant endophytic fungus Trichoderma gamsii

Three new cytochalasans, trichalasins E (1), F (2) and H (7), together with four known analogues, trichalasin C (3), aspochalasin K (4), trichalasin G (5) and aspergillin PZ (8), were isolated from one endophytic fungus Trichoderma gamsii inhabiting in the traditional medicinal plant Panax notoginseng (BurK.) F.H. Chen. Trichalasins E (1) contains a unique hydroperoxyl group, which is the first report in all known analogues, whereas trichalasin H (7) possesses the rare 6/5/6/6/5 pentacyclic skeleton with 12-oxatricyclo [6.3.1.0^2,7] moiety as that of aspergillin PZ (8). The relative configurations of the new compounds were characterized by analysis of coupling constants and ROESY correlations, and the absolute configurations of trichalasins E (1), H (7) and aspergillin PZ (8) were determined by modified Mosher’s reaction. In addition, compounds 1–5, 7 and 8 were tested cytotoxic activities against several cancer cell lines.     

Isolation, purification and identification of polysaccharides from cultured Cordyceps militaris

Four polysaccharides from the water extract of cultured Cordyceps militaris were isolated through ethanol precipitation, deproteination and gel-filtration chromatography. Their molecular weights were determined using gel-filtration chromatography. Among the four isolated polysaccharides, the structures of two of them (CPS-2 and CPS-3) were elucidated by sugar analysis, Smith degradation, IR and (13)C-NMR spectroscopy.     

枣树越冬期内生真菌的分离鉴定及抑菌研究

为了明确越冬期枣树组织中内生真菌的种类和分布情况,并从中筛选出对枣缩果病病原有拮抗作用的内生菌株,从越冬期健康枣树的树皮、枣股、枝条中分离获得内生真菌225株,共鉴定出12个真菌属,其优势属为茎点霉属、链格孢属、毛壳菌属和镰刀菌属。研究结果表明:越冬期健康枣树组织中内生真菌分布普遍,种类丰富;不同品种、不同部位中内生真菌的种类和数量都有差异。室内平板对峙实验结果表明:在225株内生真菌中,有25株内生真菌对枣缩果病病原茎点霉菌1-2有抑制作用,最高抑菌率为85.45%;有14株内生真菌对病原壳梭孢菌1-5有抑制效果,最高抑菌率为76.00%;内生真菌F7和F8对两种病原菌均有抑菌效果,而且均有明显的抑菌带,这说明上述两株菌均可产生抗菌代谢物质。     

Isolation,identification and pathogenicity of Phytophthora species from declining oak stands

Within the scope of a research project on the condition of roots of declining oaks (Quercus robur, Quercus petraea), samples of fine roots and surrounding soil, specimens of stripe cankers on the stem base, and samples of stream water were examined for the presence of Phytophthora species using both baiting methods and selective agar media. At 27 sites in Germany (Bavaria, Rheinland-Pfalz, Schleswig-Holstein), Switzerland, Hungary, Italy and Slovenia the following species were isolated (mainly from soil): Phytophthora citricola, Phytophthora cactorum, Phytophthora cambivora, Phytophthora gon-apodyides, Phytophthora undulata, a species with affinity to Phytophthora drechsleri, and two additional species with close affinity to the Phytophthora cactorum group. Moreover, Pythium group P, Pythium anandrum, Pythium chamaehyphon, and many other Pythium species that have not yet been identified could be recovered. In a soil infestation test most isolates induced dieback of long root tips and necrotic lesions in the root cortex and at the root collar of Quercus robur seedlings. All Phytophthora species tested and Pythium group P caused cortical necrosis after stem inoculation of young Quercus robur trees. It could be shown in vitro that Phytophthora gonapodyides and Pythium group P were able to produce a wilting toxin. Nitrogen input and climatic changes are discussed as predisposing factors for root damage observed in the field.     

灰背杜鹃菌根真菌的分离与鉴定及DGGE的应用

应用传统的培养方法分离菌根真菌,应用ITS rDNA分子生物学手段,进行了菌株的分类鉴定,并结合DGGE(变性梯度凝胶电泳)技术对菌根真菌进行检测。传统培养得到了2种与杜鹃花菌根真菌亲缘关系十分密切的真菌,分别为Phialocephala fortinii和Epacris pulchella root associated fungus。DGGE(变性梯度凝胶电泳)技术检测到1种菌根真菌为Rhizoscyphus ericae。     

Isolation and relative stereochemistry of lippialactone,a new antimalarial compound from Lippia javanica

The aerial parts of Lippia javanica were investigated for biologically active chemical compounds present in them. Chromatographic separation of the ethyl acetate extract of the aerial parts yielded a new antimalarial α-pyrone, lippialactone (2). Lippialactone is active against the chloroquine-sensitive D10 strain of Plasmodium falciparum with an IC₅₀ value of 9.1 μg/mL, and is also mildly cytotoxic. The relative stereochemistry of lippialactone was determined by molecular modeling based on the determination of the relative configuration by quantum mechanical GIAO ¹³C chemical shift calculations.     

Pyrenocines J-M: four new pyrenocines from the endophytic fungus, Phomopsis sp

Four new pyrenocines, named pyrenocines J-M (1-4), were isolated from an endophytic fungus, Phomopsis sp, by a bioassay-guided method. The structures of the new compound have been assigned from 1H and 13C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. Preliminary studied showed that compounds 1, 2 and 4 showed good antifungal, antibacterial, and algicidal properties, while compound 3 had good antibacterial and algicidal properties.     

Isolation and identification of the antibacterial active compound from petroleum ether extract of neem oil

From a petroleum ether extract of neem oil (Azadirachta indica A. Juss) the new tetrahydrofuranyl diester 1 was isolated as an anti-bacterial constituent. 1 showed significant activities against three standard bacterial strains, including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enteritidis CMCC (B) 50041.     

北京地区柳树上光肩星天牛刻槽中真菌的分离和鉴定

文章首次利用加入链霉素的PDA培养基，从光肩星天牛在旱柳上不同时期的30个刻槽中分离到89株14个属的真菌，经鉴定，70株隶属于半和菌类的5目5科的11个属；19株隶属于子囊菌纲的3目3科的3个属，晚期刻槽内的真菌种类最丰富，共13种；早期最少，只有6种；中期居中，共10种。     

New clerodane diterpenoid glycosides from the aerial parts of Nannoglottis carpesioides

Three new clerodane diterpenoid glycosides with l-arabinose (1–3), together with ten known compounds including phytol-type diterpenes, cycloartane-type, ursane-type, and oleanane-type triterpenes, were isolated from the aerial parts of Nannoglottis carpesioides which a Chinese endemic genus. The structures of the new compounds 1–3 were identified based on chemical and spectroscopic studies, including one- and two-dimensional NMR, HRESIMS, UV, and IR results. Their absolute configurations were determined by the application of theory calculations of optical rotation, which were compared with the experimental data. New aglycone 1a and l-arabinose were obtained by acid hydrolysis of 1 and GC–MS analysis. The cytotoxicities of some isolated compounds against a panel of human cancer cell lines were evaluated by the MTT assay. Clerodane diterpenoides are the characteristic chemical constituents and may be used as chemical markers of the genus Nannoglottis.     

Evaluation of the anti-microbial and anti-inflammatory activities of the medicinal plants Dodonaea viscosa,Rumex nervosus and Rumex abyssinicus

The crude extracts of the leaves of Dodonaea viscosa and Rumex nervosus as well as of the root of Rumex abyssinicus were tested for anti-microbial and anti-inflammatory activities. It was observed that the three plants possess antibacterial activity against Streptococcus pyogenes and Staphylococcus aureus and strong activity against Coxsackie virus B3 and influenza A virus. In contrast, none of them exhibited anti-fungal activity. The anti-inflammatory activity test results verified that only R. abyssinicus inhibited the synthesis of prostaglandin (PG) E(2).     

苹果腐烂病菌拮抗放线菌的分离与鉴定

采用常规方法对广东省中山市采集的土样进行分离,得到放线菌293株。以苹果腐烂病菌为指示菌,通过平板对峙法和管碟法对分离菌株进行筛选。对峙法获得有拮抗效果的放线菌61株,抑菌率在50%以上的有13株,其中Z-6的抑菌率达87.2%;进一步应用管碟法对上述作用明显的菌株进行复筛,抑菌圈直径大于20 mm的菌株6株,其中Z-6菌株产生抑菌圈直径最大,为32.87 mm。抑菌谱测定结果表明,该菌株对小麦全蚀病菌、番茄灰霉病菌和稻瘟病菌抑菌效果最强,抑制率在70%以上。离体枝条测定试验中,该菌株同样表现了一定的防治效果,抑制率达32.9%。最后,本试验还对Z-6的形态特征、培养特征及生理生化特性作了研究,初步鉴定为链霉菌属(Streptomyces)的金色类群(Aureus)。     

药用植物新资源的开发途径和方法

研究了开发药用植物新资源的途径和方法，主要有：筛选民族药物，扩大药用部位，建筑亲缘关系相近的药用植物，合成，半合成及修饰活性成分结构，生物技术繁殖，利用药用植物地域性定位发展等。     

Molecular identification of the powdery mildew fungus infecting rubber trees in China

Powdery mildew is a foliar disease of rubber trees. It is one of the most important leaf diseases in rubber plantations worldwide. The causal agent of this powdery mildew, previously known as Oidium heveae, has been identified under various names. To precisely identify the causal agents of this disease, 57 conidial samples were collected from 2013 to 2017 in Hainan, Yunnan and Guangdong provinces, the main rubber tree planting regions in China. Based on morphological observations using light and scanning electron microscopy, pathogenicity testing, and nrDNA ITS and 28S sequences, Erysiphe quercicola is suggested as the only causal agent of rubber tree powdery mildew in China.     

Isolation and X-ray crystal structure of a new isoquinoline-N-oxide alkaloid from Calycotome villosa subsp. intermedia

A new isoquinoline-N-oxide alkaloid was extracted from the alkaloid fraction of a methanol extract of the seeds of Calycotome villosa subsp. intermedia. Its structure was established as 1-hydroxymethyl-6,7-dimethoxyisoquinoline-N-oxide (1) by spectroscopic techniques and X-ray diffraction analysis.